This invention generally relates to methods and systems for reading utility consumption meters, such as natural gas and electricity meters, and more particularly to such methods and systems that obtain meter information automatically by telemetering the information via telephonic communication linkages with the meters to be read.
The cost for utility services such as provision of water, natural gas and electricity delivered directly via a conduit from the source to the customer's premises or site are charged based on consumption as measured by consumption meters, or meters, located at the customer's premises. It is known to interface these meters with the utility service provider via a telephone network connected via a customer's telephone line, or customer line, to the meter. Often there is only one line or one type of line at the customer's premises. In such cases, the customer line connected to the meter is the same customer line employed by the customer's voice telephone as well as other telephonic equipment at the customer's premises. Reference should be made to U.S. Pat. No. 5,182,766 issued Jan. 26, 1993 to Garland for "Generalized Telecommunications Customer Signaling Arrangement"; U.S. Pat. No. 5,189,694 issued to Garland on Feb. 23, 1993 for "Telemetry Access Arrangement"; U.S. Pat. No. 5,394,461 issued to Garland on Feb. 28, 1995 for "Telemetry Feature Protocol Expansion"; and U.S. Pat. No. 5,509,054 issued to Garland on Apr. 16, 1996 for "Communication Switching System", which patents are hereby incorporated by reference, for the details of such methods and systems.
While these systems and methods work successfully, the inventor has now determined that there are some shortcomings that arise when the customer line has a type of service, or type of interface, that is incompatible with the type of telephonic interface of the customer meter presently installed or intended to be installed at the customer site. This potentially arises whenever there is at least one customer line that is shared by the automatic telemetering meter and the voice telephone and other telephonic equipment at the customer's premises.
So long as the voice telephone and the meter require the same interface there is no apparent problem except that meters with different types of interfaces must be produced and inventoried. In such case, if the customer line is a digital line and a meter that also requires a digital interface is installed or if the customer line is an analog line being serviced by an analog interface then a meter having an analog interface is installed.
However, if after the installation of either a digital interfacing meter or an analog interfacing meter is installed, the customer changes the type of service on the line from digital to analog or from analog to digital then, of course, the meter becomes disabled from communicating through the telecommunication network and, in effect, fails to function at least as an automatic meter with telemetering capability. Once the customer line has been changed to a type of interface with which the meter is compatible the only way that telemetering capability can be restored is by replacing the meter with another one that is compatible. Disadvantageously, this new meter is also subject to the same problem should the customer choose to change the customer line back to the original service with which the original meter was compatible but with which the new meter is not.
Meters with a digital interface are preferred over meters with an analog interface due to enhanced speed and data transmission reliability for telemetering data. However, unfortunately most customer lines are analog lines and thus cannot be used in most single customer line situations.